Lab reports are an important part of many classes in both high school and college. If you're studying sciences like chemistry, physics, or biology at some point you'll have to take a lab course, and even in the social sciences you'll likely be asked to do investigative work. But whether you're mixing chemicals, studying cells, or handing out surveys, your work isn't done once you leave the lab. Doing experiments means having to write about them, and no matter how meticulous you've been, if you can't write well about the work that you've done then your grade will suffer.

What is a lab report?

A lab report is how you present the findings of your research to your teacher. It shouldn't just be a list of your results, however. You'll need to show not only that you've done all the work needed to complete the lab, but also that you understand the underlying concepts and have a sound appreciation for how the scientific method is used to answer questions.

What's in a lab report?

There's no set format for lab reports. Often teachers will give students an outline of all the information they should include and guidelines for the organization. If you don't have a set format for your class, then you should write your report using the standard IMRAD outline. IMRAD - Introduction, Methods, Results, and Discussion - is the most common way to present the findings of any sort of investigative work (i.e., any experiment that was designed to answer a specific question).

Introduction

The introduction is where you provide the reader with any background information they need to understand your work. Usually in a lab report the introduction will be brief. For a short report, all you will need to do is explain your research question and provide your hypothesis. In longer reports, you will also need to provide some context for the research question. This might just be a short explanation of why it's important, or you might need to do a longer literature review in which you cite the work of other researchers to summarize your topic and show how it relates to larger concepts in your field.

Methods

Also called the "Material and Methods" or the "Methodology" section, this is where you show in detail how you carried out your experiment. You need to specify all the equipment you used, and the steps you went through to collect data. For a short report, this might be just a numbered list, but for longer reports you will need to be more detailed and include a discussion of how the method was chosen. A good general rule for the Methods section is that someone who reads it should have all the information they need to be able to replicate your experiment.

Results

Next up you need to give the results of your experiment. Don't just list the data, though. Instead, you should complete your statistical analysis (i.e., finding averages, t tests, r values, etc.) and pick only the most important results to include. This section should be a mix of text, tables, and figures like graphs or pictures. It's important to keep in mind that the Results section shouldn't include any sort of analysis of the data (that will come in the next section). Use clear, precise language to give your results without any bias or spin.

Discussion

After you present your data you can start discussing what it means. Restate your research question and tell whether you are able to answer it with the results of your experiment. Also state whether your hypothesis was correct, and what conclusions you were able to draw. It's also important to address any problems you had in your research. Remember, there's nothing wrong with disproving your hypothesis or getting strange data as long as you're able to provide a clear explanation for why you think that happened. Lastly, you want to discuss any new questions or avenues of research brought up by your results.

Other sections you might need to include:

References

If your lab report includes citations then you'll need to have a list of all your references or works cited.

Appendices

An appendix is used to provide the reader with information that isn't necessary to understand the work but is still useful or important. Often in lab reports for a class the teacher will ask that the raw data be included in an appendix.

How is a lab report formatted?

Issues like citations, title pages, capitalization, and spacing are covered in writing style guides. There are lots of guides out there, and which one you use will likely depend on what kind of class you're taking. Most disciplines have a preferred style guide: the biological sciences usually use CSE (Council of Science Editors) or AMA (American Medical Association) formatting; chemistry uses the ACS (American Chemical Society); psychology uses APA (American Psychological Association); and physics uses AIP (American Institute of Physics). Check with your teacher if you're not sure which one to use.

How is a lab report written?

Since you're reporting on work that's already been done, lab reports should be in the past tense and in the third person. Try to keep the writing professional - it should be clear, concise, and to-the-point without using any showy language.

When writing a lab report, make sure you devote sufficient time to the introduction and conclusion. After all that work, it can be tempting to just list your results and consider the job done, but remember that the goal of a lab report is to show your teacher that you understand the concepts and can explain the significance of your work. The focus of your report should be on your analysis and interpretation of the results: a lab report with great data but a weak discussion will likely get a low grade, but a report full of bad data that is able to explain what went wrong and why will do a lot better.